In the field of wireless communications, cognitive radio is viewed as a novel approach for improving the utilization of a precious natural resource, the radio electromagnetic spectrum.
The cognitive radio, built on a software-defined radio, is defined as an intelligent wireless communication system that is aware of its environment and uses the methodology of understanding-by-building to learn from the environment and adapt to statistical variations in the input stimuli, with two primary objectives in mind, namely highly reliable communication whenever and wherever needed, and efficient utilization of the radio spectrum.
Attaining these objectives in cognitive radio therefore involves analysis of the operating environment of communication equipment. However, conventional techniques for operating environment analysis in wireless communication systems are not sufficiently accurate for use in cognitive radio.